Optical Memory Could Speed Up the Internet

ananyo writes "Bits of data travelling the internet have a tough commute — they bounce back and forth between optical signal lines for efficient transmission and electrical signal lines for processing. All-optical routers would be more energy efficient, but their development has been hindered by a lack of optical memory devices. Now, researchers have developed just such a device (journal article abstract), paving the way towards a faster, more energy-efficient internet. The devices are based on optical cavities that can be switched between light-transmitting and light-blocking states to construct digital signals. Researchers have been working on such devices for several years, but previous versions used too much power and could not retain data long enough. The new memory cells use just 30 nanowatts of power, 300 times less than previous designs, and can retain data for one microsecond — long enough to support processing." (See also this paper on all-optical swtiches by four of the same authors.)

Comments

Re:Nonsense

[w.hamra1987]

actually no, the travel time is much shorter than that of processing. in fiber-optic networks, latency appears on the nodes.

Lack of optical memory devices?

[jovius]

The researchers seem to have missed the huge leftover stock of photographic film. Stopping it completely provides indefinite storage while spinning it 1 mega frame / second satisfies microsecond processing needs.

Re:Nonsense

[Anonymous Coward]

Umm, do you know how fast the speed of light is? It's not speed that is the issue, it's the time requires to process the light which is the issue. If it takes 5ms to process light, that means that light has to be made in pulses of 5ms or else signal is lost. Longer pulses = longer travel time in a way. That is why processing purely in optical extremely important as conversion between optical to electron and back is slow in comparison to a pure optical router. When you have lots of routers between endpoints, speed is basically reduced down to switching speed which is the true bottleneck. Remove the switching and you remove the bottleneck. Now, it won't remove the switching speed at the endpoints but it does reduce the latency from switching that occurs in between.